Mesh display of the spatial structure of the nova shell around V5668 Sgr as determined from the nebular [O III] line shapes with the SHAPE software, see Fig. 7. The four panels show different orientations of the structure, the bottom-right-hand-panel shows the nova shell placed at the PA suggested from the polarimetry and as visualised in the pyCLOUDY renderings seen in Fig. 11. If the detected polarisation has its origin in the equatorial waist then the shell should be titled at 90^o in the plane of the sky. The saddle shaped 4363 Å [O III] line feature, as well as other higher excitation species, can be understood as arising from the equatorial-ring-waist.